ADMINISTRATIVE CORE ? CORE A: PROJECT SUMMARY/ABSTRACT The BIOCARD study is a longitudinal, observational study of 349 individuals who were cognitively normal and primarily middle aged (mean age=57.1) at enrollment. The subjects have now been followed for up to 27 years. The overall objectives of the project are to further advance the study of preclinical Alzheimer?s disease by: (1) clarifying the pattern and rate of change in AD biomarkers (including those based on CSF, blood, MRI, and PET imaging) and cognition; the biomarkers to be studied include several promising novel biomarkers derived from blood, CSF and brain imaging. (2) maximizing our data by working collaboratively with several research groups who have comparable data, and (3) providing a publicly accessible data, brain scans, and biological specimens, for researchers in the field. To accomplish these goals we established 7 Cores and, with this application, are also including 2 projects. The Administrative Core (Core A) is responsible for the overall functioning and coordination of the project. The specific aims include: (1) oversight and integration of the Cores and the Projects, (2) assistance with subject retention and oversight of the recruitment of additional participants, (3) collaboration with investigators outside of Johns Hopkins University, (4) assurance of sound fiscal management, (5) assurance that all aspects of the project comply with local and federal regulations, (6) coordinating external review of the project through meetings of the Scientific Advisory Board and the Resource Allocation Committee, and (7) communicating with the staff of the National Institute on Aging about the progress of the study.